Actually, there is the makings of a word thread () here. Discovered this on the old "words with unusual etymologies" thread":

Re origin of "pumpernickel" involving Napoleon's horse:

Random House and American Heritage give about the same etymology. This is RH: [1750-60; < G Pumpernickel orig., an opprobrious name for anyone considered disagreeable = pumper (n) to break wind + Nickel hypocoristic form of Nikolaus Nicholas (cf. NICKEL); presumably applied to the bread from its effect on the digestive system]

pumper?...for fart? Which leads us to other synonyms or euphemisms for fart...pass wind, passing wind, break wind, breaking wind...others?